Electrosurgery is the application of a high-frequency electric current to biological tissue as a means to cut, coagulate, desiccate, or fulgurate tissue. It enables precise cuts with limited blood loss due to a combined cutting and coagulation procedure. Electrosurgical devices are therefore frequently used during surgical operations helping to prevent blood loss in hospital operating rooms.
In electrosurgical procedures, the tissue is heated by an electric current in the tissue. The current is created by a high frequency generator, in particular a radio frequency generator to which the electrosurgical instrument is connected.
Electrosurgical instruments exist in different shapes and for different purposes. Examples are forceps, loop electrodes, scissors, pencils, scalpels etc.
Electrosurgical instruments can be classified in at least two different groups, namely monopolar instruments and bipolar instruments. The monopolar instruments works by transmitting a current from an electrode which is manipulated by a handle to an electrode which is attached to the body of the patient, typically adhesively attached. Within the context of the present application the term “bipolar electrosurgical instrument” is to be understood as an electrosurgical instrument where both electrodes are manipulated by the handle and therefore both forms part of the handheld part of the electrosurgical instrument itself. The flow of electricity is substantially confined to the space between the opposite electrode faces of the electrosurgical instrument, such as e.g. bipolar forceps or bipolar loop electrodes, so that tissue damage is substantially confined to tissue situated between said electrodes. Since no dispersive electrode is required remote from the patient, less electrical current is needed to obtain the same effects than when using monopolar electrosurgical instruments, where the current must pass through the body to get to the dispersive electrode.
Within the context of the present application the term “bipolar electrosurgical generator” is synonymous with a high frequency generator, in particular a radio frequency generator, for use with a bipolar electrosurgical instrument. A “bipolar electrosurgical generator” may thus also be a multipurpose electrosurgical generator with both monopolar and bipolar functions. Within the context of the present application bipolar or monopolar electrosurgical generators and bipolar or monopolar electrosurgical instruments can be used.
Before surgery the surgeon will have to select a power output level which is suitable for the instrument which is used. Depending on the generator which is used, the surgeon may have to live with the voltage amplitude level, or the surgeon may have to adjust the voltage amplitude level as part of the adjustment procedure. The setting may typically be based on guidelines made by the provider, as well as other indications such as previous experiences and other kinds of safety regulations. During the surgical procedure, in particular when operating on thick or large tissue objects, such as the cervix or uterus, the surgeon may benefit from increased voltage level in order to overcome the resistance through the actual tissue. Under other circumstances the surgeon may need to lower a presumed too high voltage level. Until now the solution for obtaining increased or lowered voltage is to use an appropriate electrosurgical generator and/or to amend the settings on the generator. This may, however, be inconvenient, not least if the generator is subsequently or mainly to be used with another setting. In worst case, the practitioner who subsequently uses the generator with another instrument may forget to set back the changed settings. Further, it may generally be disturbing for the surgeon having to remember to adjust the settings depending on the instrument which is being used, and the availability of different instruments requiring different settings in one operating room may be a cause of confusion and potential errors.
Generally, there is a need to develop cost-saving electrosurgical techniques and instruments towards eliminating unintended effects and limitations related to their uses.